Alert archive / Alabama / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 78, NWS Birmingham, AL

May 21, 1990Colbert County, Franklin County, Lauderdale County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at May 21, 1990, 7:24 AM CDT for Colbert County, Franklin County, Lauderdale County, Alabama. It was in force for 36 min.

The area

The counties it named.

The facts

Issued: May 21, 1990, 7:24 AM CDT (12:24 UTC)
Expired: May 21, 1990, 8:00 AM CDT
In force: 36 min
Issued by: NWS Birmingham, AL
Area: Whole counties

Counties Colbert County, AL, Franklin County, AL, Lauderdale County, AL

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 0.4 hours before the alert went out and 193 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 183 J/kg
Mixed-layer CIN: -65 J/kg
Mixed-layer LCL: 677 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: -5 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KHSV 211225
SVRHSV
ALC033-059-077-211330-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HUNTSVILLE AL
724 AM CDT MON MAY 21 1990
 
THE NATIONAL WEATHER SERVICE IN HUNTSVILLE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  830 AM CDT
IN NORTH ALABAMA...
 
IN NORTH ALABAMA
 
   ...COLBERT COUNTY...FRANKLIN COUNTY...LAUDERDALE COUNTY
 
HUNTSVILLE RADAR AT 721 THIS MORNING INDICATED A BAND OF POSSIBLE
SEVERE THUNDERSTORMS FROM NORTHWEST OF FLORENCE ALABAMA SOUTHWARD
TO THE SOUTHWEST CORNER OF FRANKLIN COUNTY.
 
THESE THUNDERSTORMS WERE MOVING EAST AT AROUND 45 MPH AND WILL
PASS NEAR FLORENCE...MUSCLE SHOALS...AND RUSSELLVILLE DURING THE
NEXT HOURS.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

The office that day

Everything else NWS Birmingham, AL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 7:01 PM CDT	Flash Flood Warning	BMX	Tuscaloosa	59 min
May 20, 7:06 PM CDT	Severe Thunderstorm Warning	BMX	Lawrence	39 min
May 20, 7:34 PM CDT	Severe Thunderstorm Warning	BMX	Limestone, Morgan	26 min
May 20, 7:55 PM CDT	Severe Thunderstorm Warning	BMX	Madison	35 min
May 20, 8:32 PM CDT	Severe Thunderstorm Warning	BMX	Morgan	43 min
May 21, 8:36 AM CDT	Severe Thunderstorm Warning	BMX	Lamar	54 min
May 21, 9:34 AM CDT	Severe Thunderstorm Warning	BMX	Pickens	41 min
May 21, 10:59 AM CDT	Severe Thunderstorm Warning	BMX	Pickens	46 min
May 21, 11:18 AM CDT	Severe Thunderstorm Warning	BMX	Chilton, Shelby	57 min
May 21, 11:32 AM CDT	Severe Thunderstorm Warning	BMX	Greene	58 min
May 21, 11:37 AM CDT	Severe Thunderstorm Warning	BMX	Talladega	38 min

Nearby

Severe Thunderstorm Warnings in Alabama, 1990 Every severe thunderstorm warning in 1990

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.